Pavement.



s. 'BL0ME.& W. J. sm'

EIS

PAVEMENT.

` APPLICATION FILED JULY13, 1911.

fatanted June 11, 1919a RUDOLPH S. BLUME AND=WILL3CA`M BUEDLPH S. BLUME CUMFANY, 0F CHICAGO, ILLNIS, J9. AJELI'NERSHP.

PAVEMENT.

Specification of Letters Patent.

Patented June itil Llllilr?.

Application led July 113, 1911. Serial No. Gflo.

To all whom it may cmwernr Be it known that We, RUnOLeH S. BLUME and li'iLLig-xiu J. Sirven, citizens ot' the lnited fltates, residing at Chicago, in the county of Cook and State of Illinois, have invented certain'new and useful improvements in Pavenlents, of which the following is a specification .lt has been customary and usual hereto- :tore in constructing concrete pavements to la),r such pavements in arched or crowned shape of substantial uniform thickness on a correspondingly curved ground foundation. le yhave discovered, however, that better results are attainable in a pavement of this character if .it is laid on a suhstan tially dat or horizontal ground foundation, the curved, or crowned contour of the top surface ofthe pavement losing secured. by making auch pavement thicker at the middle ot the roadway and of less thickness 'at the curbs, the depth of thickness gradually decreasing'from the center of the roadway to the edges. Paven'ients constructed in this manner eliminate from them any sulostantial tendency,to crackl longitudinally along the center, because of the increased thickness at such party of the pavement, and further, owing to the fact that the traftic is heavier on the central portion of the pave-- ment as distinguished from the gutter parts, a pavement laid in the manner speci.` fied conforms more nearly' to the actual working requirements ot' tuallic conditions.

Another t'eature of our invention resides in the bonding?` or attachment of a suitable surfacing of relatively small thickness to the main lood)v of the pavenlent so as to do away with the tendency .otsuch surfaeing to slide or travel down thesuriace of the v naveinent toward the gutters and also to eliminate Vthe tendency which such thin surfacing exhibits to become separated from the top of the pavement as hy linking, due to the lifierence in contraction and expansion of the composition Coi'lstituting` the surfacing and the body of the pavement proper.

In order that a t'ull and complete compro hens-ion ot this invention may he had lu' those skilled in the arl. we have illustrated. in the acconuianvingg drawingi .toi-inliner a part of this speciticalinn .i desirable uinhodiinenl of the invention, and throughouti tialj;

the various views of this drawing like reference characters apply to the salue parts.

ln the drawing Figure l, is a 'vertical cross-section through a pavement einhodving our invention; Fig. 2 is a fragmentary plan of the pavement, a portion of the .same having the top surfacing removed to more clearly illustrate the manner of bonding' such surfacing to the top of the pavement proper, this diagram showing essentially the minimum diameter of the circular locking recesses; Fig'. 3 is an enlarged erossssoction on line 3, 3, Fig. 2; Fig. -l-is an enlarged cross-section on line l. l, F 2; and Fig. :"5 is a similar cross-section on line 5, of Fig. 2.

B v reference to this. drawing it will be observed that the top of the ground founder tion l() between the oomhined gutters and curbs 1l, 1l, is suhstantia.lliY dat and horizontal. The pavement under ordinalv circumstances can he laid directlyion such 'lint top of the ground except in the eiilder climates where the underlying grounffl or soil is composed ot clay or `other similar heavy material, and waere the effects of the elements must he -taken into account. lfn der sneu eirciunstances we provide a drainage or `loundation to prevent any detrimental aotion ot the cold weather, so that the frost wilhnot crack or cause un upheaval ot the pavement. The pavement proper laid between the curbs and on the ground consists iueirahly of a lower or underlying stratum l2 desirahljv composed ot one part of Portland cement and eight parts of an aggregato v fonsist-ing cent. ot' what is known as il inch stone and gravel with :ll particles helow a halt inch eliminated. 'l por eentfof l' inch hard stone or gravel. and. 25.5 per cent. ot clean torpedo sand. Such conerete is laid and compacted in the usual manner and on the same is superposed an upper layer t3 composed ot one part of `Hartland cement, one part of coarse torpedo sand, and one part ot' a mass ot hard r'iarticles or' pieces auch as broken Istone. ,egraveh Congloinerale` hard slag. or similar hard substantie equal i ,nantily to the volume ot sund, i This` mass consists desirahljv' ot lil per cent. ot' il, inch size, ')Oper cent. oit inch size. and 2i) per rent. of .l inch size, the ii'igredients having sulistu all liner or smaller parta-ier oit pen or bonding* ci such thin top surface of the pavement proper has not been secured. To improve such union or bonding constitutes one of the objects of this invention and ive accomplish it by passing over the top of the layer i3, after the concrete has become set sufficiently for the purpose in view, aliand roller provided with suit-able projections and ribs to form in the surface of the concrete a series of distinct separated recesses or cavities is vvith'at bottoms l5 and directly connected together by grooves 16 and also connected together by the intersecting grooves i? and i8, all of such grooves being preferably 'tf-shape in cross-section,as shown in Fig. 5. These cavities and grooves are desirably made snilostantiallyv inch in depth, (aithcngli this may be varied, of course, to snit different conditions, and I sometimes prefer to mal/te the cavities somewhat deeper than the grooves and also greater in diameter and of other shapes than as shown in the drawing) and ,then the top surfacing of suitable material such as paving pitch, bituminous substance, a coal tar product desirably luxed with a. small amount of coal tar, or asphalt properly fluxed is applied, so that the top of thepavernent vvill have a surfacing substantially inch thick, but such surfacing will have downwardly-extended' projections and ribsfitti'g into the corresponding cavities, recesses, and grooves in pavement pro'l'er, so that a firm-'and secure anchorage is directly effected-for the limited thickness of coatingrnaterial. In this Way the very thin top surfacing is effectivcly bonded and united with the pavement in such a manner that it cannot be-, come detached or shift in position. Thissurfacing is desirably'etna` dark color so thatunder bright light it'wvill not have ai detrimental or objectionable eii'e'ct on the eyes. Such an anchoring of the surfacing to'the concrete pavemcntis desirable in summer when the top coating becomes more pliable and has a tendency to shift; on the pavement, and is also desirable inthe Winter When this top surfacing becomes more rigid. The fitting of the ribs and projec- -Where the pavement is provided with such a curb.

While we have herein specified the various amounts 'and parts of ingredients of the pavement and have'set `forth in detail the different dimensions and also the shapesandI arrangements ot' the recesses and grooves, it is to be understood that our invention is not limited to these precise and exact details because they can be varied within wide limits Without departure from the heart of the invention and Without the sacrifice of any material or substantial benefits accruing from the invention.

Vhat We claim is:

l. A- pavement including a foundation provided with loneitudinal parallel grooves extending throughout the length oi the pavement, transverse parallel grooves eX- tending the entire width ot' the pavement, diagonal parallel grooves extending throughout the Width oit the pavement and cross ing the other grooves at their points of intersection, and cavities at each of the in tersections of the several grooves, the Walls of such cavities being vertical, and a surfacing 0n top of the foundation and extend ing into the grooves and the cavities, substantially as described.

2. A pavement including Aa foundation provided on its top surface with intersecting V-shaped grooves, and cavities at the intersections of the grooves, the walls of said cavities being sul'istantially vertical, and a surfacing on top ofthe foundation and extending intopthe grooves and the cavities, substantially 'as described.

3. A' .pavement including a foundation provided'with longitudinal, transverse, and diagonalintersecting V-shaped `grooves, and

.cavities at the intersections of the grooves,

the Walls of such cavities being substantially vertical, and a surfacing on top ot the :foundation and extending into the grooves and the cavities, substantially as described.

RUDOLPH 'eroina lVILLlM J. SINEK. Witnesses:

S. GiNsnUnG, M. C. GOODWIN. 

